1. Field of the Invention
This invention relates to an oil retriever and method of use therefor for recovering heavy oil, including Bunker C, from a surface of a body of water, such as oceans, lakes, rivers and the like and in particular to an oil retriever that is maneuverable independently on water and can operate efficiently to assist in cleaning up oil spills where the heavy oil has been formed into a sticky cohesive mass by cold water.
2. Description of the Prior Art
It is known to have oil retrieving equipment whereby a basin is suspended from a floating vessel, the basin having an open top surrounded by a lip. The basin is positioned so that the lip is just below the surface of the oil and the oil flows into the vessel. The oil is then pumped from the vessel to a storage tank. The floating vessel does not work very well with heavy oil, particularly when the oil is in cold water, as the oil cannot be efficiently pumped. Also, if the vessel is not suspended accurately at the correct depth, more water than oil will enter the vessel. Heavy oil is sometimes removed from a water surface by a plurality of strands of fiber formed into a conveyor belt. The fiber strands soak up the oil from the surface and the fiber is then passed through a set of rollers where the oil is removed and placed in a storage tank. This procedure can be very inefficient as the fibers sometimes contact the water and absorb water rather than oil. It is also known to use partially submerged, hydraulically-operated, perforated steel belts which are suspended from the bow of a vessel. The oil collects in the perforations in the belts and is transferred to a storage tank. Another known recovery unit is an open top well that is supported by floats. An annular overflow weir floats at the well rim allowing the oil and water to fall into the center. Water is pumped continuously from the bottom of the well while a second pump removes oil from the top of the well as and when a sufficient amount of oil has been collected. Chemicals have also been developed to disperse oil into small droplets whereby it can decompose naturally. Of course, the chemical added to the water to disperse the oil further pollutes the water and must be removed.
Previous oil recovery or dispersal systems can suffer from an extreme drop in efficiency when used with heavy oil, particularly when the heavy oil is located in cold water. Further, the efficiency of previous recovery systems can be greatly reduced when the water is choppy or waves are present. Also, previous recovery systems are expensive, complex or messy. Pollution of waterways through oil spills is becoming much more of public concern. From the recent Alaskan oil spill, where numerous cleanup personnel worked on various beaches with hand-held cloths to scrub the rocks, it can be seen that current oil recovery equipment is not satisfactory.